Benign prostatic hyperplasia is one of the most common chronic conditions among America men. The traditional, `gold standard', surgical treatment is transuretheral prostatectomy (TURP). However, during the last decade the use of minimally invasive surgical treatments (MIST procedures) such as transurethral microwave thermotherapy (TUMT), laser therapy, and transurethral needle ablation therapy (TUNA) have become increasingly common. We have recently determined that the number of MIST procedures performed in elderly male Medicare beneficiaries increased from 17,791 in 1999 to 112,788 in 2005, a 634% increase. Concurrently, the number of transurethral prostatectomies (TURPs) performed in this population decreased by 29% from 104,363 to 73,356. These two different trends have resulted in over a 50% increase in surgeries performed for BPH in this population in just 6 years, form 128,415 in 1999 to 193,555 in 2005. Initially, this study will examine the use of the MIST procedures from 1999 through 2006 for men 65+ years of age in more detail. We will describe and compare the socio-demographic characteristics of those receiving MIST therapy compared with those who receive TURPs, including a comparing the rates between Whites and minority group members. We will then describe important events requiring care by a urologist following the MIST procedures including post-operative diagnostic tests, re-operations with the same or another MIST procedure or TURP, and other post-operative therapeutic interventions for up to 7 years following the surgeries. Comparisons of the rates of these events following different MIST procedures will be made, as well as between each MIST procedure and TURP. We will also report the costs of different types of BPH surgery, including pre- and post-operative care. We will compare these costs between each MIST procedure, as well as between each MIST procedure and TURP for up to seven years post BPH surgery. We will also calculate the total annual costs to Medicare for BPH surgery for the years 1999 through 2006. Finally, we will examine possible changes in urologic practice during this period. We will compare the time from the diagnosis of BPH to surgical treatment for incident cases of BPH diagnosed early (1999) and later (2004) in the study period. Also, using the soon to be available Medicare Part D (prescription drug) data, we will compare the rates of use of medical therapy prior to each type of surgical treatment in 2006.7. PUBLIC HEALTH RELEVANCE: The efficacy of minimally invasive surgical treatments (MIST procedures) has been demonstrated in clinical trials;however, their effectiveness and clinical impact in the general population, as well as the impact of their remarkable increase in popularity on the health care system, are not known. Traditional measures of effectiveness (as opposed to efficacy) such as the outcomes of these procedures in typical practice settings, the cost implications for individual cases and health care payers such as Medicare, their availability and access to (as measured by utilization) these new procedures among traditionally disadvantaged populations (those of minority race or ethnicity, for example), and the effects on the practice patterns in urology need to be studied.